AS Associate Of Science In Physics 1 — Questions and Answers
Question 1: What does Newton's second law of motion state?
- An object in motion stays in motion unless acted upon by a net force
- Force equals mass times acceleration (Correct answer)
- For every action there is an equal and opposite reaction
- Force equals mass divided by velocity
Correct answer: Force equals mass times acceleration
Newton's second law states F = ma, meaning the net force on an object equals its mass multiplied by its acceleration.
Question 2: A car travels 150 km in 3 hours. What is its average speed?
- 30 km/h
- 75 km/h
- 50 km/h (Correct answer)
- 45 km/h
Correct answer: 50 km/h
Average speed = distance ÷ time = 150 km ÷ 3 h = 50 km/h.
Question 3: Which of the following is a vector quantity?
- Temperature
- Mass
- Speed
- Velocity (Correct answer)
Correct answer: Velocity
Velocity is a vector quantity because it has both magnitude and direction, unlike speed which is a scalar.
Question 4: What is the approximate acceleration due to gravity near Earth's surface?
- 9.8 m/s² (Correct answer)
- 8.9 m/s²
- 10.8 m/s²
- 6.67 m/s²
Correct answer: 9.8 m/s²
The standard gravitational acceleration near Earth's surface is approximately 9.8 m/s² downward.
Question 5: What does the slope of a displacement-time graph represent?
- Acceleration
- Velocity (Correct answer)
- Force
- Momentum
Correct answer: Velocity
The slope of a displacement-time graph equals velocity, since slope = Δdisplacement/Δtime.
Question 6: According to Newton's third law, if you push a wall with 50 N, the wall pushes back with:
- 25 N
- 0 N
- 50 N (Correct answer)
- 100 N
Correct answer: 50 N
Newton's third law states that action and reaction forces are always equal in magnitude and opposite in direction.
Question 7: What is the SI unit of force?
- Joule
- Watt
- Pascal
- Newton (Correct answer)
Correct answer: Newton
The Newton (N) is the SI unit of force, defined as the force needed to accelerate 1 kg at 1 m/s².
AS Associate Of Science In Physics 1
What does Newton's second law of motion state?